The present invention relates to plugs, drains, and valves for fluid containers and, more specifically, to a removable drain plug or valve.
The oil pan of an automobile engine crankcase typically has a drain plug that is screwed into a threaded drain opening in the bottom of the pan. This plug is removed to drain the used oil. Draining the oil is typically a messy and unpleasant task because oil pours forth in an uncontrolled manner as the plug is loosened and removed, often onto the hand of the person removing the plug. Not only is this procedure messy, but the person can suffer burns if the oil is hot. For the same reasons, it is undesirable to attempt to stop the flow of oil by replacing the plug.
Practitioners in the art have invented drain plugs that have remotely-operated valves, in part to address the problem of soilage of a person's hands. For example, U.S. Pat. No. 1,830,132, issued to Quinn, discloses a valve that has a rod extending upward through the crankcase that a person can rotate from above to operate the valve. Although Quinn's invention addresses the soilage problem, an existing crankcase of conventional design cannot easily be retrofitted with Quinn's invention. Furthermore, the rod cannot extend upward through conventional crankcases due to the configuration of the engine.
U.S. Pat. No. 3,049,334, issued to Montague, discloses an L-shaped drain valve attachment that can be operated from a point beneath the crankcase. A hollow screw receives oil from the crankcase through the vertical portion of the valve body and rotates in a threaded valve body within the horizontal portion of the valve body. The screw has an axial bore that terminates in an orifice. The oil drains when the orifice emerges from the valve body as the screw is rotated. Thus, the oil will begin to spout in whatever direction the orifice is oriented as soon as a portion of it emerges from the valve body. Since the orifice emerges gradually as the screw is rotated, the valve may briefly spout oil in a circular path, soiling both the underside of the automobile and the area in which the automobile is located, until the orifice can be aligned to direct the flow into the desired receptacle below the crankcase. Furthermore, excessive rotation of the screw would result in its inadvertent removal from the valve body.
A threaded plug that can be retrofitted into existing oil pans or other fluid containers, that can be used to effectively control fluid flow and direction, and that cannot be inadvertently removed would be highly desirable. These problems and deficiencies are clearly felt in the art and are solved by the present invention in the manner described below.